带有webHttpRelayBinding和REST / JSON和POST的Azure中继服务总线

Question

The following article explains how to build an simple WCF service with Azure Relay Service Bus: https://azure.microsoft.com/en-us/documentation/articles/service-bus-dotnet-how-to-use-relay/ The example shows the use with TCP Binding. I reproduced it and it works flawless. Now I want the same with webHttpRelayBinding but it does not work as expected. I split the code the service in a common dll, a WCFServiceWebRole project, and command line host (as alternative to web.config) and clients :

common dll with interface definition and settings file with bus key, namespace and protocol (tcp or http) namespace WCFRelayCommon { using System.ServiceModel; using System.ServiceModel.Web;

    [ServiceContract(Namespace = "urn:ps")]
    public interface IProblemSolver
    {
        [OperationContract
        WebInvoke(UriTemplate = "/solver", Method = "POST",
            RequestFormat = WebMessageFormat.Json, ResponseFormat = WebMessageFormat.Json,
            BodyStyle = WebMessageBodyStyle.Wrapped)]
        int AddNumbers(int a, int b);
    }

    public interface IProblemSolverChannel : IProblemSolver, IClientChannel { }

    public enum BusProtocol { tcp, http };

    public class Utils
    {   
        public static BusProtocol Protocol
        {
            get
            {
                BusProtocol mode;
                if (!Enum.TryParse(AzureSettings.Default.Protocol, out mode))
                {
                    throw new ArgumentException("wrong input, exiting");
                }
                return mode;
            }
        }
    }
}

WCFServiceWebRole project. I first defined all service settings (behavior, biding) in the Web.config and thus should be self sufficient as is.

namespace WCFServiceWebRoleRelay
{
    public class ProblemSolver : WCFRelayCommon.IProblemSolver
    {
        public int AddNumbers(int a, int b)
        {
            return a + b;
        }
    }
}

But I also defined an alternative host project with all settings by code, easier to debug. So just a command line project using the settings file. 2 implementations: either with NetTcpRelayBinding or with WebHttpRelayBinding. with secure transport.

namespace WCFRelayHost
{
    class Program
    {
        static void Main(string[] args)
        {
            var transportClientEndpointBehavior = new TransportClientEndpointBehavior
            {
                TokenProvider = TokenProvider.CreateSharedAccessSignatureTokenProvider("RootManageSharedAccessKey", AzureSettings.Default.BusKey)
            };

            ServiceHost sh;
            switch (Utils.Protocol)
            {
                case BusProtocol.http:
                    sh = CreateWebHost(AzureSettings.Default.BusNamespace, transportClientEndpointBehavior);
                    break;
                case BusProtocol.tcp:
                    sh = CreateTcpBindingHost(AzureSettings.Default.BusNamespace, transportClientEndpointBehavior);
                    break;
                default:
                    throw new Exception("wrong mode");
            }
            sh.Open();
            Console.WriteLine("Press ENTER to close");
            Console.ReadLine();
            sh.Close();
        }

        static ServiceHost CreateTcpBindingHost(string busNamespace, TransportClientEndpointBehavior transportClientEndpointBehavior)
        {
            Uri tcpAddress = ServiceBusEnvironment.CreateServiceUri("sb", busNamespace, "solver");
            ServiceHost sh = new ServiceHost(typeof(ProblemSolver));            
            var binding = new NetTcpRelayBinding(EndToEndSecurityMode.Transport, new RelayClientAuthenticationType());            
            return AddServiceEndpoint(sh, binding, tcpAddress, transportClientEndpointBehavior);
        }

        static ServiceHost CreateWebHost(string busNamespace, TransportClientEndpointBehavior transportClientEndpointBehavior)
        {
            // https://<namespace>.servicebus.windows.net/solver
            Uri webAddress = ServiceBusEnvironment.CreateServiceUri("https", busNamespace, "solver");
            var binding = new WebHttpRelayBinding(EndToEndWebHttpSecurityMode.Transport, new RelayClientAuthenticationType());
            WebServiceHost wsh = new WebServiceHost(typeof(ProblemSolver), webAddress);
            return AddServiceEndpoint(wsh, binding, webAddress, transportClientEndpointBehavior);
        }

        static ServiceHost AddServiceEndpoint(ServiceHost sh, Binding binding, Uri uri, TransportClientEndpointBehavior transportClientEndpointBehavior)
        {
            sh.AddServiceEndpoint(typeof(IProblemSolver), binding, uri).Behaviors.Add(transportClientEndpointBehavior);            
            return sh;
        }
    }
}

And the client command line app.

namespace WCFRelayClient
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Enter 2 numbers to add separated by space");
            var line = Console.ReadLine();
            var array = line.Split(' ');
            int first, second;
            if (!int.TryParse(array[0], out first) || !int.TryParse(array[1], out second))
            {
                Console.WriteLine("wrong input, exiting");
            }
            else
            {
                Console.WriteLine("Wait the host to run, press ENTER when ready to send the request");
                Console.ReadLine();

                var transportClientEndpointBehavior = new TransportClientEndpointBehavior
                {
                    TokenProvider = TokenProvider.CreateSharedAccessSignatureTokenProvider("RootManageSharedAccessKey", AzureSettings.Default.BusKey)
                };

                IProblemSolverChannel ch;
                switch (Utils.Protocol)
                {
                    case BusProtocol.http:
                        ch = WebBinding(AzureSettings.Default.BusNamespace, transportClientEndpointBehavior);
                        break;
                    case BusProtocol.tcp:
                        ch = TcpBinding(AzureSettings.Default.BusNamespace, transportClientEndpointBehavior);
                        break;
                    default:
                        throw new Exception("wrong mode");
                }
                Console.WriteLine(ch.AddNumbers(first, second));
                ch.Dispose();
            }

            Console.ReadLine();
        }

        static IProblemSolverChannel TcpBinding(string busNamespace, TransportClientEndpointBehavior transportClientEndpointBehavior)
        {
            var binding = new NetTcpRelayBinding(EndToEndSecurityMode.Transport, new RelayClientAuthenticationType());            
            var uri = ServiceBusEnvironment.CreateServiceUri("sb", busNamespace, "solver");
            return CreateChannel(binding, uri, transportClientEndpointBehavior);
        }

        static IProblemSolverChannel WebBinding(string busNamespace, TransportClientEndpointBehavior transportClientEndpointBehavior)
        {
            var binding = new WebHttpRelayBinding(EndToEndWebHttpSecurityMode.Transport, new RelayClientAuthenticationType());
            var uri = ServiceBusEnvironment.CreateServiceUri("https", busNamespace, "solver");            
            return CreateChannel(binding, uri, transportClientEndpointBehavior);
        }

        static IProblemSolverChannel CreateChannel(Binding binding, Uri uri, TransportClientEndpointBehavior transportClientEndpointBehavior)
        {
            var cf = new ChannelFactory<IProblemSolverChannel>(binding, new EndpointAddress(uri));
            cf.Endpoint.Behaviors.Add(transportClientEndpointBehavior);
            return cf.CreateChannel();
        }
    }
}

I just have to change the setting parameter to http or tcp to use either webHttpRelayBinding or netTcpRelayBiding

As said, with netTcpRelayBiding, the code run as expected.

With webHttpRelayBinding, I get a InvalidOperationException in mscorlib

System.InvalidOperationException was unhandled
HResult=-2146233079
  Message=Manual addressing is enabled on this factory, so all messages sent must be pre-addressed.
  Source=mscorlib

What did I miss? Maybe some configuration on the Azure Portal? I just followed the instructions from the tutorial...

Answer 1

I was able to get your example working in "http" mode by changing WCFRelayClient.Program.CreateChannel method to use WebChannelFactory<T> when dealing with WebHttpBinding/WebHttpRelayBinding:

static IProblemSolverChannel CreateChannel(Binding binding, Uri uri, TransportClientEndpointBehavior transportClientEndpointBehavior)
{
    ChannelFactory<IProblemSolverChannel> cf;
    if (binding is WebHttpBinding || binding is WebHttpRelayBinding)
    {
        cf = new WebChannelFactory<IProblemSolverChannel>(binding, uri);
    }
    else
    {
        cf = new ChannelFactory<IProblemSolverChannel>(binding, new EndpointAddress(uri));
    }

    cf.Endpoint.Behaviors.Add(transportClientEndpointBehavior);
    return cf.CreateChannel();
}

If you are sending with some HTTP Client other than the *HttpRelayBinding and your relay endpoint requires client authentication then you need to build the SAS Token and put the authorization into the HTTP Authorization header.

NodeJs, JAVA, PHP, C# examples and general description of how to build the SAS Token: https://azure.microsoft.com/en-us/documentation/articles/service-bus-sas-overview/

This page appears to have a Javascript example (I haven't verified it works): http://developers.de/blogs/damir_dobric/archive/2013/10/17/how-to-create-shared-access-signature-for-service-bus.aspx